Isolation and Purification of Polysaccharide A from Isatidis indigotica and Study on Its Structure / 中国药房

ABSTRACT

OBJECTIVE: To extract and isolate Isatidis indigotica polysaccharide A(with uniform molecular weight) and to study its structure.METHODS: Hydrosoluble crude polysaccharides were extracted from Isatidis indigotica before being separated and purified by column chromatography to obtain polysaccharide A.The purity and relative molecular weight of polysaccharide A were determined by high performance gel chromatography(HPGPC) and the chemical structure each polysaccharide constituent was studied by UV detection,IR spectral analysis,NMR detection,periodate oxidation and Smith degradation methods.RESULTS: The average molecular weight of polysaccharide A was 11 700.Arabinose and galactose were the major monosaccharide;? was the major configuration of glycosidic bond was predominantly,and 1→3 was the main linkage while 1→4 and/or 1→2 linkages were also presented in polysaccharides A.CONCLUSION:Isatidis indigotica polysaccharides A is a new compound,and its purity remains as high as above 96%.